Hydraulic switch and signal apparatus



' (No Model.)

J.. A. ZINN. HYDRAULIC SWITCH AND SIGNAL APPARATUS. No. 449,240. Patented Mar. 31, 1891.

21.1mm! A T UNITED STATES PATENT OFFICE.

JOHAN AUGUST ZINN, OF ALTOONA, PENNSYLVANIA.

HYDRAULIC SWITCH AND SIGNAL-APPARATUS.

i-SPEGIIFICATION forming part of Letters Patent No. 449,240, dated March 31, 1891. Application filed October 18, 1887- serial No. 252,695. (No model.)

To aZZ whom it may concern:

Be it known that LJOHAN Aucosr ZINN, of Altoona, county of Blair, State of Pennsylvania, have invented a new and useful Improvement in Switch and Signal Apparatus,

of which the following is a true and exact description, due reference being had to the accompanying drawing, which forms a part thereof.

My invention has reference to switch and signal apparatus; and it consists in certain improvements, all of which are fully set forth in the following specification, and shown in the accompanying drawing, which forms part thereof.

This invention relates to a construction of hydraulic switch and signal apparatus set out in my application, Serial No. 224,818, and

- filed January 19, 1887. In that application the switches or signals are operated by a plunger working in a cylinder, which cylinder receives a liquid, and said liquid'is caused to flow under pressure in a manner to eject the plunger. The pressure is caused by pumping it through an accumulator, and the flow of the liquid is controlled by means of a suitable valve device, which in practice is connected with the interlocking mechanism. The liquid flows through pipes, and in return- 3 ing the plunger to reset the switch or signal the actuating-liquid which has passed through a valve device is allowed to escape through a I stand-pipe into a tank maintaining a con stant pressure, such as is necessary for keep- 3 5 in g all of the operative compartments or tubes full of the operating-liquid. V In this application my object is to employ the same system combined with an additional feature whereby in returning the switch or signal to its nor- 0 mal position gravity or springs shall not be relied upon, but instead a hydraulic device shall be resorted to to act upon the plunger in the opposite direction to that in the other cylinder.

In carrying out my invention I arrange two cylinders, preferably in line, with a doubleended plunger common to both cylinders, whereby if a plunger enters one cylinder it is drawn out of the other, and vice versa.

This plunger is connected directly or indirectly to a switch or a signal. One of these cylinders connects with the hydraulic mechanism above described and set out in my application above referred to, and the other of said cylinders connects with a second accumulator of less power than the one in the system for positively operating the switch or signal. From this construction it is evident that when the stronger accumulator, or that connecting with the interlocking mechanism, is in operative connection with one of the cylinders at the switch or signal the plunger is forced into the other cylinder, returning the liquid from said cylinder back into a main connecting with the smaller accumulator, the piston thus acting by means of a differential pressure upon its two ends. When the stronger accumulator is cut out of action and the actuating-liquid allowed to flow into the stand-pipe, then the weaker accumulator comes into action and returns the plunger to its normal position; It is evident that this double construction of cylinders is nothing more or less than the equivalent of a single cylinder with the pressure of the two accumulators upon the respective sides of the piston.

In the drawing is shown a diagrammatic View giving the relation of the operating parts and illustrating the invention as ap plied to both a switch and a signal.

A is the force-pump, which draws a supply of liquid from the tank S by means of a pipe U. This liquid is pumped by means of pipes B and M into the accumulators C and N. Pipe M is normally closed by a stop-cock m, and liquid is only admitted into the accumulator N when the liquid is low and needs to be replenished. The accumulator 0, being more heavily loaded than the accumulator N, consequently exerts the greater pressure. The liquid forced through the pipe B enters the valve-box D with the pressure of the accumulator C, and if the lever 01 is thrown to the position indicated the valve E will be opened and valve F closed. This will allow the liquid to flow from pipe B through valve E into the pipe G, and thence act upon a piston h in a cylinder H. Connecting with this cylinder H upon the other side of the piston h is the line-pipe I, which extends from the signal-house to the switch or signal operating mechanism J. The pipe M, connecting with the smaller accumulator, extends to the 5 switch or signal operating mechanism J 5 but said pipes I and M connect with separate cylinders.

Referring now to the switch or signal operating mechanism, preferably arranged di- I rectly at such switch or signal and marked J in the drawings, we have the two cylinders J and J with a plunger K, the ends of which project into said cylinders, so that when the plunger is pushed out of one cylinder it is I received into the other cylinder, and vice versa. To the plunger K is connecteda crosshead 7c, which is bolted to the bar Z, connecting the points of the switch L, or in case of the signal 0 this cross-head his connected to the vertical rod P, which in turn operates the semaphore-arm R. The semaphore-arm R is counterbalanced by a weight '1", so as to be easily moved'in either direction. As shown in the drawing, the pipe I connects with the switch-operating device and with the signaloperating device by means of the pipe 2, and likewise the pipe M connects also with the signal-operating device bya pipe m. This is correct if the signal 0 and the switch L are operated together, or, which often is the case, two or more signals or two or more switches by one lever; but in case where a signal is to be operated alone then the switch device would be removed entirely, or vice versa.

T is the stand-pipe, which, when the valve E is closed and F is open to cut oif the liquid from the accumulator 0, receives the liquid from pipe G through valve F and discharges it into the tank S with a uniform back-press- 4o ure.

So far as the invention is concerned, it is evident that the liquid from pipe G might pass directly into pipe I; but where a number of switches and signals .are to be operated 5 on the interlocking principle it is found necessary to use the intermediate piston h,which controls the flow of oil or other liquid in the pipe I. The particular specific function of this piston and its connections is clearly shown and claimed in my application above referred to, and in this application I make no claim to this construction, other than that the same is necessar to the operativeness of this device.

It is evident that the cylinder J receives the pressure of the accumulator 0, whereas the cylinder J 2 receives the pressure of the accumulator N, and when both of these accumulators are in active operation then the plunger K moves in view of the differences in the pressures. hen the valve E is closed and F opened,the accumulator N is the only one in operation, and that operates against the pressure in the stand-pipe T alone, and

55 with a positive force returns the switch or signal, or both, to theirnormal or initial position. It is immaterial to myinvention what uid to one side or end of the plunger or piston, a

pipe-line for supplying a pressure-liquid to the other side or end of the plunger or piston, a pressure device to supply said liquid to each of said lines of pipe, but under different pressures, an overflow stand-pipe, and a valve device for allowing thevliquid from the pipe having the greatest operative pressure to pass into the overflow-pipe, reducing the pressure in the pipe having the greatest operative pressure.

2. In a switch or signal operating device, the combination of the switch or signal, a plunger or piston for actuating said switch or signal, a pipe-line for supplying a pressure-liquid to one side or end of the plunger or piston, a pipe-line for supplying a press ure-liquid to the other side or end of the plunger or piston, a pressure device to supply said liquid to each of said lines of pipe, but under different pressures, an overflow stand-pipe, a valve device for allowing the liquid from the pipe having the greatest operative pressure to pass into the overflow stand-pipe, reducing the pressure in the pipe having the greatest operative pressure, and valve mechanism to admit or cut off a fresh supply of liquid undera high pressure to the pipe having the greatest operative pressure.

3. The combination of a switch or signal, a differential hydraulic operating mechanism for directly operating said switch or signal, two lines of pipe for supplying liquid under different pressures, an accumulator to each of said pipes, but of different powers, an overflow stand-pipe, and a valve device to cut ofi the stronger accumulator from its pipe and open the pipe to the overflow stand-pipe.

4. The combination of a switch or signal, a differential hydraulic operating mechanism for directly operating said switch or signal, two lines of pipe for supplying liquid under different pressures, an accumulator to each of said pipes, but of different powers, an overflow stand-pipe, a valve device to cut off the stronger accumulator from its pipe and open the pipe to the overflowstand-aipe, a forcepump to supply liquid under pressure to the stronger accumulator, and a supply-connection from the tank to the pump.

5. The combination of a switch or signal, a differential hydraulic operating, mechanism for directly operating said switch or signal, two lines of pipe for supplying liquid under different pressures, an accumulator to each of said pipes,but of difierent powers, a cylinder in the pipe in connection with the stronger accumulator, and a piston in said cylinder re- IIC ceiving on one side the liquid which extends to the switch or signal and on the other the liquid which extends to the accumulator.

6. The combination of a switch or signal, a differential hydraulic operating mechanism therefor, pipes I, G, and 13, including the valve-box D and accumulator C, and pipe M, including the accumulator N, the accumulator N being of less power than M.

7. The combination of a switch or signal, a differential hydraulic operating mechanism therefor, pipes I, G, and B, including the valve-box D, cylinder H, having the piston h and accumulator C, and pipe M, including the accumulator N, the accumulator N being of less power than M. 7

8. The combination of a switch or signal, a diiferential hydraulic operating mechanism therefor, pipes I, G, and B, including the valve-box D and accumulator O, pipe M, in- 2 U to supply liquid from tank S to the pump. 2 5

J. AUGUST ZINN.

Witnesses:

WALTER VIELTSABER, E. M. PROSSER. 

